Mobile phones have become so common that we wonder how we lived without them, but what do you do when your child's mobile bills take on a life of their own? In this extract from our archives, parenting expert and child psychologist Dr Pat Spungin, CEO of Raisingkids.co.uk, offers advice.

Raisingkids member's problem
My 13 yr-old is spending all her money on her phone bills. I thought a mobile would give her more freedom of movement but it's getting out of hand.

We tried Pay-As-You-Go but switched to monthly bills as the tariff is lower. She knows paying the bill is her responsibility but her pocket money won't stretch. She earns between seven and ten pounds a week doing household chores, but obviously this money comes out of the household budget. She keeps dipping into her Post Office savings account but I'm not very happy about this. How do I teach her to control her spending without taking away her independence?

Dr Spungin's advice
Is her mobile a necessity? How did she manage before? It's fun, but it's not one of life's essentials. Is she spending all her pocket money on her phone bills? If so, it adds up to over £500 a year - not an insignificant sum of money! Consequences are the best teacher. You won't teach her to control her spending if she knows you'll cough up the extra cash when she overspends. If you tell her she's got to pay her way, that should make her stop and think! There's no incentive to limit the calls if you're always going to pick up the tab.

Let her find the solution. Tell her she'll have to pay for all her calls and suggest that she comes up with an affordable alternative solution. Text messages are cheaper than calls so perhaps she should rely on SMS more. If she has cheap internet access, how about sending messages from free SMS sites. Pay-As-You-Go is self-limiting and looks like the best idea but don't give her ready-made solutions. These are all possibilities but, most importantly, get her to work out the solution to the problem for herself. In the jargon, if she 'owns the problem' she's more likely to find and stick to a solution.

You can't always get what you want and the bottom line is that she can't have something if she can't afford it. It's an important lesson to learn - especially in these days of easy credit. However, it's a good thing that she's prepared to earn her pocket-money with chores rather than just asking for handouts. You don't want to discourage this attitude! If you can afford it, offer her a little extra money for a little extra work. If you can't afford it, might she be able to organise a limited amount of paid work with friends or relatives, such as washing granny's car or weeding the next-door neighbour's garden?

Start now with a problem-solving approach to issues that arise between you both. Change your way of talking to her, encourage her to discuss and solve her own problems (with your help). In this way, you give her increasing control and responsibility and start a dialogue that will serve you well through the next few years, as she pushes for more independence. Good luck!

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